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General History of Electrical Transmission in California

California's rugged terrain and often early scattered pockets of population made the transmission of power an important factor in the state's development. Mining settlements and cities quickly used up all easily accessible combustibles for steam power, and bringing in more from other sources was expensive and difficult. Mining communities discovered that nearby water sources could produce electricity that was easily transmitted to rugged isolated sites.1 The problem was that the first electrical systems popularized by Thomas A. Edison were direct current (DC) and had a limited transmission distance. Most mining communities could find a hydroelectric site within transmission distance, but cities and agricultural communities often could not.

The nature of this problem and its solution led to the great electrical battle between Westinghouse, building systems around high voltage alternating current (AC), and Edison, building systems around DC electricity. Westinghouse acquired patents for transformers from other inventors and a very important patent for poly-phase alternating current generators and motors from Nicola Tesla. The system his engineers devised used transformers to increase or "step up" the voltage, and at this higher voltage electricity could be transmitted longer distances with less loss. At the receiving end, another transformer would decrease or "step down" the voltage to a level suitable for use. Edison countered that the high voltages were unsafe and took the battle to the public with demonstrations of electrocutions. The two firms battled it out in public and the academic press and contract bids for the Columbia Exposition in Chicago and engineering and equipment bids for a proposed hydroelectric power plant at Niagara Falls. While the battle raged over safety in the east, in the west there was no question of suitability.

California was introduced to AC by former Brush Electric Company engineer Almerian Decker. Decker came to California in 1891 for his health and became involved in a southern California electrical project. Decker and his partners, Cyrus G. Baldwin and Henry Harbison Sinclair, opened the San Antonio Light and Power Company in 1892 using Westinghouse technology to transmit power over 14 miles to Pamona. Decker then went on to design Mill Creek, the first commercial American three phase power plant.2 In 1895, the Folsom power plant, designed by James Lighthipe of General Electric, supplied power to Sacramento 22 miles away. These projects were all completed before the eastern states recognized the value of long distance transmission demonstrated by the Niagara project.3

California electrical companies, especially Eugene J. de Sabla and John Martin's companies, continued to increase transmission voltages and distances. Bay Counties Power Company, owned by de Sabla and Martin, broke records in 1901 when they transmitted power generated in the Sierra-Nevada to San Francisco. Throughout the early 20th century California companies developed the hydropower resources of the mountains and transmitted the power across the state.

The shortage of oil and increasing demands for electricity during World War I challenged electrical companies to make more energy available without building more plants. The California State Railroad Commission and the Committee on Petroleum of the State Council on Defense suggested in 1917 that the companies integrate their transmission lines. These integrated lines would allow unused power from one source to be used elsewhere where generating capacity was not as large. This idea of interconnected generating pools was adapted both in the northeast and in neighboring western states following the California model.4

The post-World War II era was a time of rapid growth in California. Housing and populations swelled along with the business and industrial concerns. Fueled by wartime defense industries, California grew rapidly. Northern California utility Pacific Gas & Electric (PG&E) began a program of generation growth that included both hydroelectric and steam power. Steam turbine power plants were cheaper and quicker to build than hydroelectric plants and utilities companies moved away from hydroelectricity, establishing steam turbine power as the generator of choice. Such plants conserved water and kept costs down for the business and the consumer.5 The design criteria were the same in all cases: build the facility close to load centers to reduce transmission costs; locate near fuel supplies; locate near a water supply; and select a site where land was cheap and could support a good foundation. Even with these advance in technology and despite being closer to population centers, steam plants still needed transmission facilities and substations were constructed throughout the service area to connect the new power plants.6


  1. James C. Williams, Energy and the Making of Modern California (Akron, Ohio: University of Akron Press, 1997) p.173.
  2. James C. Williams, Energy and the Making of Modern California, 175.
  3. James C. Williams, Energy and the Making of Modern California, 176-7.
  4. James C. Williams, Energy and the Making of Modern California, 245.
  5. Myers, Iron Men and Copper Wires, 200; James C. Williams, Energy and the Making of Modern California, 277-78, 282-83.
  6. James C. Williams, Energy and the Making of Modern California, 284, 374.

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